JP6646160B2 - Abrasion-resistant composite material, its application to a cooling element of a metallurgical furnace, and its manufacturing method - Google Patents

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application claims priority and benefit of US Provisional Patent Application No. 62 / 296,944, filed February 18, 2016, the contents of which are incorporated herein by reference.

  FIELD OF THE INVENTION The present invention relates generally to cooling elements for metallurgical furnaces, such as blast furnace stave coolers and tuyere coolers, and more particularly, to a layer of a composite material comprising wear-resistant particles arranged in a matrix of thermally conductive metal. And a cooling element having a working face provided with a cooling face.

  Various types of metallurgical furnaces are used for metal production. The process usually involves high temperatures and the products are molten metal and process by-products, generally slag and gas. The furnace wall may be lined with a cooling element, typically comprising copper or cast iron, and may include internal flow paths for circulating a coolant, typically water. For example, the walls of a blast furnace are typically lined with water-cooled cooling elements, such as stave coolers and / or tuyere coolers.

  The stave cooler is subject to wear caused by contact with the hot abrasive present inside the furnace. For example, in a blast furnace, a stave cooler is in contact with a descending charge including coke, limestone flux, and iron ore. The descending raw material is hot and contains particles of various sizes, weights and shapes, the hardness of which is higher than that of the materials typically used to make staves. As a result, stave coolers are prone to wear, and worn stave coolers typically shut down. This means that no cooling is performed and the stave is completely degraded. This can cause the furnace shell to overheat, which in turn can cause the furnace shell to burst.

  Tuyere coolers are subject to erosion of the inner wall due to the gas-enriched carbon-based solids, and are also subject to wear and erosion of the outer wall due to contact with unburned carbon-based solids and molten metal droplets. As a result, the tuyere cooler is very susceptible to wear and, consequently, water leakage. A worn tuyere cooler must be shut down and replaced, since a broken tuyere cooler reduces furnace productivity and distorts the circumferential symmetry of the hot air jet. This causes production losses and increased throughput using other tuyere coolers, which also increase the likelihood of failure and are prone to financial losses due to reduced production.

  Attempts have been made to improve the wear characteristics of stave coolers. For example, it has been proposed to attach the wear-resistant element to the contact surface of a copper stave or to apply a wear-resistant coating to the contact surface by rotary friction welding.

  It has also been proposed to disperse the cured particles throughout the entire volume of the cooler (e.g. JP 2001-102715A). However, this approach places the majority of the wear-resistant particles in areas of the cooler that are not subject to wear and can be uneconomical due to the relatively high cost of hardened particles. Also, since these particles are small and dispersed throughout the cooling element, it is difficult to diagnose in a non-destructive manner whether they are present on the hit surface with sufficient density.

  It has also been proposed to insert a wear resistant material into the bottom of the matrix before casting the stave cooler (WO 79/00431 A1). Suggested materials include hard aggregates, such as tungsten carbide carbide, or stainless steel expanded metal mesh.

  However, simply placing the wear-resistant material on the bottom of the mold does not guarantee that it will be reliably placed on the contact surface of the cooler with sufficient density, so that the wear-resistant material is evenly distributed over the contact surface. It is difficult to manufacture a cooling element having the following. This is acceptable for plate coolers that can be easily replaced from outside the blast furnace, but not for stave coolers that cannot be replaced without extending downtime.

  There remains a need for furnace cooling elements having improved wear characteristics to improve furnace operating efficiency and minimize downtime while maintaining the cost and manufacturability of the cooling elements.

  In one aspect, a cooling element for a metallurgical furnace is provided. The cooling element has a body including a first metal, the body having at least one surface along which a facing layer is provided. The facing layer comprises a composite material, the composite material comprising abrasion resistant particles disposed in a matrix of a second metal, wherein the abrasion resistant particles are higher than the hardness of the first metal and the second metal It has a hardness higher than that of.

In another aspect, there is provided a method of manufacturing the cooling element disclosed herein. This method
(A) providing a designed arrangement of the wear-resistant particles; and (b) defining the designed arrangement of the wear-resistant particles in a mold cavity, defining the facing layer of the cooling element. (C) introducing a molten metal into the mold cavity, wherein the molten metal comprises the first metal of the body of the cooling element and the molten metal of the composite material. Including a second metal;
including.

The present invention will now be described by way of example only with reference to the accompanying drawings.
The figure which shows the structure of a blast furnace. FIG. 2 is a front perspective view of the stave cooler according to the first embodiment. FIG. 3 illustrates the various facing layer configurations shown in FIG. 2, wherein each of FIGS. 2A-2H includes an enlarged view of a region circled to more clearly show the shape of the wear-resistant particles. . The front perspective view of the stave cooler by a 2nd embodiment. The front perspective view of a tuyere cooler. FIG. 3 is a diagram illustrating wear-resistant particles having various shapes. It is explanatory drawing which shows the square area packing and the hexagonal area packing of spherical wear-resistant particles in a composite material. FIG. 4 illustrates an alternative embodiment of the face-to-face configuration for the stave cooler shown in FIG. 2, including an enlarged view of the area circled to more clearly show the shape of the particles.

  FIG. 1 is an explanatory view showing a general blast furnace. The blast furnace is constructed in the form of a high-rise structure having a steel shell 10 surrounding an inner lining containing refractory bricks and cooling elements.

  Blast furnaces operate according to the counterflow exchange principle. The charge, including coke, limestone flux and iron ore column 6, is charged from the top of the furnace and has a high temperature flowing upward through a porous charge from a tuyere cooler 1 located at the bottom of the furnace. Reduced by gas. The descending charge is preheated in the throat section 5 and then travels through two oxygen reduction zones, namely a ferric oxide reduction zone or "stack" 4, and an iron oxide reduction zone or "furnace" 3 Reach It then falls to the hearth 9 via the melting zone or “Bosch” 2, where the tuyere cooler 1 is located. Then, the molten metal (pig iron) and the slag are tapped from the perforated openings 8 and 7.

  FIG. 1 shows a plurality of tuyere coolers 1 arranged in the area of the lower furnace part “Bosch” 2. The tuyere cooler 1 is circumferentially spaced apart in close proximity to the other to form a ring. The spacing is typically symmetric. The tuyere cooler 1 functions as a protective shell of the hot air injector into the furnace, thereby providing a continuous axisymmetric fuel injection and extending the operating life of the blast furnace.

  The stave coolers are generally located adjacent to one another in the furnace belly 3, stack 4 and throat 5 of the blast furnace and form the cooled inner surface of the furnace. The stave cooler acts as a thermal protection medium for the furnace shell 10 by accumulating accumulated charge, thereby maintaining the structural integrity of the furnace wall and preventing rupture. Cooling generally requires convective heat exchange between cooling fluids (usually water) flowing in cooling channels embedded within the stave body.

  The cooling element according to the first embodiment includes a stave cooler 12 having a general structure as shown in FIG. The stave cooler 12 comprises a body 14 made of a first metal, the body 14 having one or more internal cavities defining one or more internal coolant passages 16 (see cutouts in FIG. 2). And a flow passage 16 is provided through a plurality of coolant conduits 18 having a length sufficient to extend through the furnace shell 10 (FIG. 1), a coolant circulation located outside the furnace. It is in communication with a system (not shown).

  The body 14 of the stave cooler 12 has at least one surface 20 along which a facing layer 22 is provided. In the embodiment shown in FIG. 2, the surface 20 comprises a contact surface 24 of the cooler 12, also referred to as a “hot face”, which is directed into the interior of the furnace and is exposed for contact with the charge descending column 6. (FIG. 1). The hitting surface 24 of the stave cooler 12 of FIG. 2 is shown as having a corrugated structure defined by a plurality of horizontal ribs 26 and a plurality of horizontal valleys 28 alternating along the hitting surface 24. I have. This corrugated structure assists in maintaining a protective layer of charge on the contact surface 24.

  FIG. 2 shows a cooling element in the form of a stave cooler 12 for a blast furnace, but the embodiment disclosed herein wears due to contact with hard particulate abrasive in a metallurgical furnace. It will be understood that the invention is generally applicable to various configurations of cooling elements.

  FIG. 3 shows the schematic structure of a cooling element according to a second embodiment, including a stave cooler 12 ', where the same reference numerals as those used in connection with the previous embodiments apply where appropriate. Has been used to identify similar functions.

  The stave cooler 12 'includes a body 14 made of a first metal, the body 14 having one or more internal coolant passages 16 (see cutouts in FIG. 3). A cavity is provided and the flow path 16 is connected to a coolant located outside the furnace via a plurality of coolant conduits 18 having a length sufficient to extend through the furnace shell 10 (FIG. 1). It communicates with a circulation system (not shown).

  The body 14 of the stave cooler 12 'has at least one surface 20 along which a facing layer 22 is provided. In the embodiment shown in FIG. 3, the surface 20 comprises a contact surface 24 of the cooler 12 ', also called "hot face", which is directed into the furnace and is exposed for contact with the charge descending column 6. are doing. In contrast to the stave cooler 12 shown in FIG. 2, the abutment surface 24 of the stave cooler 12 'of FIG. 2 is shown as having a substantially flat flat surface having a relatively low height or depth. Have been. Thus, in the present embodiment, substantially the entire contact surface 24 of the stave cooler 12 'is exposed to be in contact with the charge descending column 6.

  FIG. 4 shows the schematic structure of a cooling element according to a third embodiment with a tuyere cooler 42, where the same reference numbers as those used in connection with the previous embodiments correspond to the case where applicable. Has been used to identify similar functions.

  The tuyere cooler 42 may include a body 44 that includes a frusto-conical hollow shell open at both ends. The body 44 includes a side wall 50 that defines a frustoconical shape of the body 44, the side wall 50 having an outer surface 51 and an inner surface 60. In the side wall 50, a plurality of internal coolant passages 46 are provided between the outer surface 51 and the inner surface 60 (see the notch in FIG. 4), and the coolant passage 46 is provided in the furnace shell 10 (see FIG. 4). It communicates with a coolant circulation system (not shown) located outside the furnace via a plurality of coolant conduits 48 having a length sufficient to extend through 1).

  As shown in FIG. 4, an outer surface facing layer 52 is provided on a part of the outer surface 51 of the side wall 50, and the outer surface facing layer 52 is provided on a first contact surface 54 of the stave cooler 42. The first contact surface 54 is on the outer surface of the stave cooler 42 and is directed upward. Applying the outer face-to-face layer 52 on the first abutment surface 54 is accomplished by contacting the falling charge in the furnace with the unburned carbon-based solids and molten metal droplets, resulting in the top of the cooler 42 being contacted. The purpose is to reduce wear and erosion of the opposing parts.

  The outer facing layer 52 is also provided on the inwardly facing end face 58 of the stave cooler 42 and defines a second contact surface 59. End face 58 includes an annular end face of side wall 50 surrounding a central opening through which stave cooler 42 injects air into furnace Bosch 2 (FIG. 1). End face 58 is also exposed to contact the descending charge, unburned carbon-based solids, and molten metal droplets.

  The inner surface 60 of the side wall 50 defines a third contact surface 62 of the cooling element 42, on which an inner facing layer 64 is provided, to enhance the polishing effect of hot air blast containing entrained abrasive solids such as carbonaceous solids. The resulting wear along the inner surface 60 of the side wall 50 is reduced.

  The bodies 14, 44 of the cooling elements 12, 12 ', 42 described above comprise a first metal having sufficient thermal conductivity and a melting point high enough to allow use in a metallurgical furnace. The first metal comprises any metal conventionally used in cooling elements of metallurgical furnaces, including cast iron, steel, including stainless steel, copper, copper-nickel alloys such as Monel® alloys. Can be. The bodies 14, 44 may be formed by casting with a casting sand mold or a permanent graphite matrix, and may be machined one or more times after casting. The coolant channels 16, 46 in the body may be formed during or after casting.

  Table 1 below compares the hardness of the first metal of the coolant with the hardness of the various components of the furnace charge. Table 1 shows that the hardness of the raw material components is generally higher than the hardness of the metal. If left unprotected at the contact surfaces 24, 54, 59 of the cooling elements 12, 12 ', 42, the first metal of the bodies 14, 44 will have the following two at the contact surfaces 24, 54, 59, 62: It will be worn by at least one of two mechanisms: direct wear and gas driven particle blast / erosion. Direct wear is caused by the downwardly moving charge particles, in particular the direct friction between the charge on the outer surface of the cooling element 12, 12 ', 42 and at least one of the contact surfaces 24, 54, 59. Caused by sliding contact. Gas driven erosion is caused by blasting due to particles driven by gas flowing upward from the tuyere 1. The gas becomes faster as it passes through the narrow channel, carrying small particles of the charge that rub off the outer abutment surfaces 24,54,59. Further, the third (inside) contact surface 62 of the stave cooler 42 is rubbed and worn by the high velocity gas flowing through the hollow interior of the stave cooler 42 carrying small abrasives such as sprayed coke.

  In the stave coolers 12, 12 'disclosed herein, the first metal of the body 14 is protected by a facing layer 22 provided along at least one surface 20 of the body 14, where The at least one surface 20 may comprise a part of the contact surface 24 of all the cooling elements 12, 12 '. For example, in some embodiments, at least one surface 20 may be limited to a vertical surface of horizontal rib 26 that partially defines abutment surface 24 in stave cooler 12 shown in FIG. In the stave cooler 12 'shown in FIG. 3, at least one surface 20 on which the facing layer 22 is provided may include the entire contact surface 24 of the cooler 12'.

  In the tuyere cooler 42, the outer surface facing layer 52 is provided along a part or the whole of the first and second contact surfaces 54 and 58 located on the outer surface of the main body 44. An inner surface facing layer 64 is provided along at least a portion of the inner surface 60 of the side wall 50 and defines a third contact surface 62.

  The facing layers 22, 52, 64 comprise a composite material, the composite material comprising abrasion resistant particles disposed in a second metal composite material. The wear-resistant particles have a hardness greater than the hardness of the first metal comprising the bodies 14, 44, and can desirably have a hardness of at least about 6.5 Mohs, which value As can be seen from Table 1, it is above the maximum hardness of the components of the charge.

  For example, the wear-resistant particles of facing layer 22, 52, 64 may include one or more wear-resistant materials selected from ceramics including carbides, nitrides, borides and / or oxides. it can. Specific examples of carbides that can be incorporated into the composite include tungsten carbide, niobium carbide, chromium carbide, and silicon carbide. Specific examples of nitrides that can be incorporated into the composite include aluminum nitride and silicon nitride. Specific examples of oxides that can be incorporated into the composite include aluminum oxide and titanium oxide. Specific examples of borides that can be incorporated into the composite include silicon boride.

  The abrasion resistant particles and materials listed above are high in strength and have a hardness greater than 6.5 Mohs. For example, each of the carbides listed above has a hardness of 8-9 Mohs. The wear-resistant particles and materials listed above are at least as hard as any material commonly encountered in metallurgical furnaces, including the components that make up the charge in blast furnaces. Further, at least some of the wear resistant particles and materials, such as tungsten carbide, have a relatively high thermal conductivity, which is described in more detail below.

  The second metal comprising the matrix of facing layers 22, 52, 64 may optionally have the same composition as the first metal comprising the bodies 14, 44 of the cooling elements 12, 12 ', 42. For example, the second metal may be made of cast iron, steel including stainless steel, copper, and copper alloy including copper-nickel alloy such as Monel (registered trademark) alloy.

  In one embodiment, the second metal comprising the matrix of facing layers 22, 52, 64 comprises a high copper alloy having a copper content of 96% by weight or more. The inventors have discovered that pure copper is a suitable composite material for a number of reasons. For example, high copper alloys have high toughness, which makes the composite resistant to stretching and shear, and also resilient to thermal deformation. Also, high copper alloys are metallurgically compatible with many materials, and copper is well understood. Finally, high copper alloys have excellent heat transfer properties at a reasonable cost. Thus, in view of cost, manufacturability, toughness and thermal conductivity, the present inventors have discovered that high copper alloys are effective matrix materials.

  From the above description, it can be seen that the composite of facing layers 22, 52, 64 is composed of two distinct components (i.e., wear-resistant particles and a second metal) having significantly different physical and chemical properties. I understand. When combined, these individual components provide different properties to the composite material than the individual components, and outperform any single material suitable for manufacturing cooling elements in metallurgical furnaces. For example, the composite can have an abrasive wear rate determined according to ASTM G65 of 0.6 times or less the abrasive wear rate of gray cast iron under the same conditions. Advantageously, the combination of properties of this composite material includes higher wear resistance and higher thermal conductivity than that achieved by traditionally used cooling elements, including cast iron staves. included.

  The thickness of the facing layers 22, 52, 64 is variable and may be from about 3 mm to about 50 mm, and the remaining portions of the bodies 14, 44 of the cooling elements 12, 12 ', 42 comprise a first metal. May be. Since the wear-resistant particles can be several times more expensive than the first metal, it is advantageous to confine the wear-resistant particles to the required facing layers 22, 52, 64. Further, because the composite material has a lower thermal conductivity than the first metal, confining it to a portion of the total thickness of the cooling elements 12, 52, 64 increases the cooling performance of the cooling elements 12, 52, 64. The effect of the composite material can be minimized.

  In addition to the composition of the particles and the second metal, the overall thermal conductivity and wear resistance of the composite will depend on the interaction between the particles and the composite, which will be described below. It depends on a number of factors. Thus, the composite of facing layers 22, 52, 64 can be tailored to have a specificity suitable for a range of applications.

  In this regard, the composites described herein can include a macro-composite metal, where the wear-resistant particles are impregnated into the second metal composite to produce optimal wear resistance. And are arranged in accordance with a substantially designed arrangement.

Substantially disposed designed repeated macros composite has a unit volume is estimated to be a cubic shape having a length of the edge "a" and the volume "a ^3". The length of the edge of the cube defines the exterior size of the repeating designed arrangement and may be from about 3 mm to about 50 mm. The edge length "a" is determined such that a single wear-resistant particle, regardless of its shape and orientation, falls within the package size of the repetitive designed arrangement. Accordingly, the macrocomposite is defined herein as comprising abrasion resistant particles having a size of about 3 mm to about 50 mm, for example, about 3 mm to about 10 mm. For spherical or substantially spherical particles, the particle size is determined by the particle diameter. For all particles, regardless of shape, particle size is defined as the minimum outer dimension of the wear-resistant particles.

  Abrasion-resistant particles of relatively large size can be detected by conventional ultrasonic testing equipment used for quality control of cast copper cooling elements, so that the abutment surfaces 24 of the stave coolers 12, 12 'and the blades The non-destructive test can be used to determine whether a sufficient concentration of wear-resistant particles is present on the contact surfaces 54, 58, 62 of the mouth cooler 42.

  The factors governing the interaction between the wear-resistant particles and the matrix are described below.

  1. Volumetric packing factor of abrasion resistant particles in a unit volume of macrocomposite material

Volume filling ratio of the abrasion resistant particles in the unit volume of macro composite material can be varied both between 0 to 100% is defined as the ratio of the volume V of the wear-resistant particles per unit volume a ³ You.

Volume filling rate = V / a ³

  The higher the volume filling ratio of the wear-resistant particles, the higher the ratio of the wear-resistant particles to the matrix. Designed arrangements of substantially repeating macrocomposites require adequate volume balance for sufficient thermal conductivity and sufficient wear resistance. In this regard, the higher the percentage of wear-resistant particles in the macrocomposite material, the more wear-resistant material over the contact surfaces 24, 54, 58, 62 and facing layers 22, 52, 64. , Higher wear resistance is obtained. Conversely, because the wear-resistant particles are less conductive than the first metal, the higher the proportion of wear-resistant particles in the macrocomposite, the lower the thermal conductivity of the macrocomposite.

  2. Front area filling rate

Frontal area filling ratio of the wear-resistant particles in the unit volume a ³ can be varied in the range of 0 to 100% on the Euclidean plane, in practice the range of about 20-100%. The frontal area fill factor is defined as the ratio of the projected area of the abrasion resistant particles (PA) to the projected area of the unit volume.

Area filling rate = P. A. / A ²

  A high area packing factor of the abrasion resistant particles leads to a higher abrasion resistance and lower thermal conductivity of the macrocomposite. Therefore, in order to obtain sufficient thermal conductivity and appropriate abrasion resistance within the repeating macrocomposite material, an appropriate area filling factor is required.

  3. The ratio of the area of the abrasion-resistant particle / matrix interface to the volume of the macrocomposite material

  The contact interface area or contact surface area between the wear-resistant particles and the second metal of the matrix represents the bonding area between the wear-resistant particles and the matrix; A. As shown. More because there are many areas that conduct heat between the wear-resistant particles and the matrix, and there are more areas in the matrix that form strong metallurgical bonds that hold the wear-resistant particles Is advantageously present. The relationship between the shape and volume of the wear-resistant particles is governed by the ratio of surface area to volume.

Ratio of surface area to volume = S. A. / A ³

S. A. Is small enough to be 0 when there is no contact between the aggregate and the matrix, and has substantially no upper limit when there is a large contact area. Adequate metallurgical bonding, retention of wear-resistant particles and enhancement of wear resistance are necessary to prevent the loss of wear-resistant particles. The present inventors have, for the proper performance of the macro composites minimum interfacial surface area of 0.25a ² (S.A.) and / or 0.1 minimum surface area to volume ratio (S.A./ a ³ ) should be present.

  4. Existence of continuous copper tendrils surrounding wear-resistant particles

  Within the macrocomposite material, most of the heat transfer is by conduction through a metal matrix made of a second metal. Accordingly, the metal matrix includes metal tendrils surrounding the wear-resistant particles and extending "parallel" toward the abutment surfaces 24, 54, 58, 62 of the facing layers 22, 52, 64. It is desirable. These tendrils improve the cooling of the macrocomposite and prevent melting and the resulting collapse of the composite.

  To explain the above principle, it can be inferred using an electric circuit with resistors connected in parallel and in series. A resistor connected in series produces a higher current resistance than a resistor connected in parallel. Heat behaves similarly. Accordingly, metal tendrils having relatively low thermal resistivity must each extend continuously on the contact surfaces 24, 54, 58, 62 between the wear resistant particles having relatively high heat resistance. In addition, it must extend continuously from the contact surfaces 24, 54, 58, 62 over the entire thickness of the facing layers 22, 52, 64. This is similar to a resistor connected in parallel, where the total resistance is lower overall. On the other hand, if the metal tendril extends parallel to the contact surfaces 24, 54, 58, 62 between the layers of wear-resistant particles, the total thermal resistivity is additive and the heat transfer is relatively poor. .

  5. Shape of wear-resistant particles and their relative spatial orientation in macrocomposites

  The shape of the wear-resistant particles affects each of the factors listed above. In addition, the shape and orientation of the wear-resistant particles affect the tribological interaction between the contact surfaces 24, 54, 58, 62 and the opposing surfaces (ie, the charge), as described below. Effect.

  The less contact between the contact surfaces 24, 54, 58, 62 and the opposing surfaces, the lower the friction and therefore the less wear, abrasion, wear and erosion of the contact surfaces 24, 54, 58, 62. The use of wear resistant particles having a spherical, cylindrical, curved or other deflected shape has beneficial results in this regard. When the shape and orientation of the abrasion resistant particles are optimized, the opposing surfaces are deflected therefrom without substantially damaging the abutment surfaces 24, 54, 58, 62. This reduces the likelihood of both wear and erosion at the contact surfaces 24, 54, 58, 62.

  The wear-resistant particles should be properly anchored within the matrix to resist shear and bending loads induced by one or more movements, such as slipping, rolling, rolling, and the like. Therefore, any wear-resistant particles located on the contact surface should extend into the matrix by at least 0.25 of their full length or diameter.

  Considering the material selection and all the above factors, and selecting the optimal value according to the usage environment, the macro composite defined herein has good wear resistance and thermal conductivity characteristic values. To achieve. The wear resistance of the macrocomposite is measured by the abrasion rate using the standardized ASTM G65 test, and the thermal conductivity of the composite is measured on a% IASC scale and in W / mK. Cast iron and copper are the two most widely used material options for the first metal of the bodies 14,44 of the cooling elements 12,12 ', 42. Table 2 below shows a conventional stave cooler made entirely of cast iron or copper, and a body 14,44 made using the macrocomposite material described herein and containing copper. The thermal conductivity and wear resistance of the stave cooler are compared. Table 2 shows that cooling elements 12, 12 ', 42 having facing layers 22, 52, 64 comprising a macrocomposite material as defined herein have better thermal conductivity than conventionally configured cooling elements. It clearly shows that it has a high rate of wear and abrasion resistance.

  To illustrate the effect of the aforementioned factors on the properties of the macrocomposite, several samples of the macrocomposite were devised. Table 3 and FIGS. 2, 2A to 2H, FIGS. 5-1, 5-8 and 7 show these examples. For purposes of illustration, FIG. 2 shows several different types of macrocomposites provided on several ribs of stave cooler 12. The ribs having these various macrocomposites are labeled 26-1 to 26-8 in FIG.

  2A to 2H show the facing layer 22 of each of the ribs 26-1 to 26-8 in more detail. Each of the facing layers 22 shown in FIGS. 2A-2H shows an engineered configuration of a macrocomposite material having differently shaped abrasion resistant particles 66, wherein the abrasion resistant particles 66 in each of these figures are: , Arranged in a substantially repeating designed arrangement. It will be appreciated that the substantially repeated designed arrangement of particles 66 is interspersed with a matrix 70 of a second metal. The matrix 70 is not shown in FIGS. 2A-2H for clarity.

  FIGS. 5-1 to 5-8 each show one unit volume of the macrocomposite material shown in FIGS. 2 and 2A-2H, and of the second metal forming the tendrill 68 as described above. A portion of the matrix 70 is also shown. In each of FIGS. 5-1 to 5-8, arrow 74 defines a first direction in which tendril 68 extends through matrix 70 to surface 20 of facing layer 22; Extends parallel to the surface 20 as shown in FIG.

Example 1-Spherical Wear-Resistant Particles As shown in FIGS. 2, 2A and 5-1, this sphere has an advantageous tribology because it has essentially a single contact with no notches and grooves. It has a typical shape. Thus, the cooling elements 12, 12 ', 42 comprising facing layers 22, 52, 64 of macro-composite material incorporating the spherical wear-resistant particles 66 provide for the contact between the charge and the cooling elements 12, 12', 42. Due to the reduced frictional sliding contact between the surfaces 24, 54, 58, 62, it is expected to exhibit low wear rates in use.

  FIG. 5-1 shows a unit volume 72 of a macrocomposite material comprising a copper matrix 70 and spherical wear-resistant particles 66 having a diameter a. The diameter a defines the envelope size of the composite unit cell and is 3-50 mm in diameter, for example 3-10 mm. The unit volume 72 of the macro composite material of this size is a material having the properties defined in Table 3. As an example, FIG. 2 shows the cooling element 12, where the facing layer 22 shown at one of the horizontal ribs 26 (reference numeral 26-1 in FIG. 2) comprises the copper matrix 70 of FIG. It includes a macro-composite material that includes the wear-resistant particles 66. The facing layer 22 may include a single layer of spherical wear-resistant particles 66 packed in a hexagonal area packing arrangement, as shown in FIGS. 2A and 6. It will be appreciated that, instead, the spherical particles 66 may be packed into a square area packing arrangement, as shown in FIG. The facing layers 22, 52, 64 of the cooling elements 12 ', 42 may have the same or similar composition and structure.

Example 2-Vertical rod-shaped wear-resistant particles A cylindrical rod oriented with a longitudinal axis perpendicular to the contact surfaces 24, 54, 58, 62 is advantageous because it acts as a beam that resists shear loads due to wear. Shape. Thus, the cooling elements 12, 12 ', 42 with facing layers 22, 52, 64 of macrocomposite incorporating rod-shaped wear-resistant particles 66 oriented perpendicular to the surface 20 have low wear rates in use. It is expected to show.

  FIG. 5-2 shows a copper bar 70 and a cylindrical rod-shaped abrasion resistant cylinder having a diameter a and a length a and oriented perpendicular to the front surface of the unit volume 72 defining the surface 20 of the facing layer 22. And a unit volume 72 of the macrocomposite material including the conductive particles 66, and forms a part of the contact surface 24, 54, 58, 62. The dimension a defines the outer size of the composite material unit cell, and is 3 to 50 mm, for example, 3 to 10 mm. The unit volume of a macrocomposite of this size is a material having the properties defined in Table 3. FIG. 2 shows the cooling element 12, in which the facing layer 22 shown on one of the horizontal ribs 26 (reference numeral 26-2 in FIG. 2) is made up of a copper matrix 70 and the cylindrical shape shown in FIG. And a macro-composite material including rod-shaped wear-resistant particles 66. The facing layers 22, 52, 64 of the cooling elements 12 ', 42 may have the same or similar composition and structure.

Example 3-Parallel Bar-shaped Wear-Resistant Particles A cylindrical rod oriented to have a longitudinal axis parallel to the contact surfaces 24, 54, 58, 62 is such that during wear, the overall length of the cylindrical rod is reduced to the opposite surface (mounting). It has an advantageous tribological shape because it acts as a deflector for the feedstock. Thus, the cooling elements 12, 12 ', 42 with facing layers 22, 52, 64 of macrocomposite incorporating rod-shaped wear-resistant particles 66 oriented parallel to the surface 20, the charge and the cooling elements 12 , 12 ', 42 are expected to exhibit low wear rates during use due to reduced frictional sliding contact between the contact surfaces 24, 54, 58, 62.

  FIG. 5-3 shows a copper matrix 70 and a cylindrical bar-shaped abrasion resistant having a diameter a and a length a and oriented parallel to the front surface of the unit volume 72 defining the surface 20 of the facing layer 22. A unit volume 72 of the macrocomposite material including the particles 66 is shown, forming part of the contact surfaces 24, 54, 58, 62. The dimension a defines the outer size of the composite material unit cell 72 and is a size of 3 to 50 mm, for example, 3 to 10 mm. The unit volume 72 of the macro composite material of this size is a material having the properties defined in Table 3. FIG. 2 shows the cooling element 12, in which the facing layer 22 shown at one of the horizontal ribs 26 (reference numeral 26-3 in FIG. 2) comprises a copper matrix 70 and a cylindrical rod of FIG. And a macro composite material including the wear-resistant particles 66. The facing layers 22, 52, 64 of the cooling elements 12 ', 42 may have the same or similar composition and structure.

Example 4 Vertical Ring-Shaped Wear-Resistant Particles Cylindrical rings (i.e., hollow cylinders) oriented to have a longitudinal axis perpendicular to the contact surfaces 24, 54, 58, 62 have sheared rings due to wear. This is an advantageous shape because it acts as a load-bearing beam. Thus, cooling elements 12, 12 ', 42 with facing layers 22, 52, 64 of macrocomposite incorporating vertically oriented ring-shaped wear resistant particles 66 exhibit low wear rates in use. Be expected. The ring shape having an inner diameter results in the formation of an additional tendril 68 in the metal matrix and additional penetration (contact surface area) between the wear-resistant particles 66 and the metal matrix 70.

  FIG. 5-4 shows a copper ring 70 and a cylindrical ring-shaped abrasion resistant having a diameter a and a length a and oriented perpendicular to the front surface of the unit volume 72 defining the surface 20 of the facing layer 22. FIG. 7 shows a unit volume 72 of the macrocomposite material including the conductive particles 66 and forming a part of the contact surface 24, 54, 58, 62. The dimension a defines the outer size of the composite material unit cell 72 and is a size of 3 to 50 mm, for example, 3 to 10 mm. The unit volume 72 of the macro composite material of this size is a material having the properties defined in Table 3. FIG. 2 shows the cooling element 12, in which the facing layer 22 shown at one of the horizontal ribs 26 (reference numeral 26-4 in FIG. 2) is a combination of the copper matrix 70 of FIG. And a macro-composite material including the wear-resistant particles 66. The facing layers 22, 52, 64 of the cooling elements 12 ', 42 may have the same or similar composition and structure.

Example 5-Plate-shaped wear-resistant particles Plate consisting of a single part or a plurality of smaller pieces adjacent to each other, arranged on the contact surfaces 24, 54, 58, 62 of the cooling elements 12, 12 ', 42 Have the advantage of overall protection, which limits the abrasive attack on the matrix material. If there is a large difference in the coefficient of thermal expansion, the smaller the fragments that are close to each other, the lower the thermal fatigue of the joint between the aggregate and the matrix. Thus, cooling elements 12, 12 ', 42 with facing layers 22, 52, 64 of macrocomposite incorporating plate-like wear-resistant particles 66 are expected to exhibit low wear rates in use. .

  FIG. 5-5 shows a unit volume 72 of the macrocomposite material along the front surface of the copper matrix 70 and the unit volume 72 having sides of length a and defining the surface 20 of the facing layer 22. A unit volume 72 comprising oriented plate-shaped wear-resistant particles 66 and forming a part of the contact surface 24, 54, 58, 62 is shown. The dimension a defines the outer size of the composite material unit cell 72, and is 3 to 50 mm, for example, 3 to 10 mm. The unit volume 72 of the macro composite material of this size is a material having the properties defined in Table 3. FIG. 2 shows the cooling element 12, in which the facing layer 22 shown on one of the horizontal ribs 26 (reference number 26-5 in FIG. 2) is connected to the copper matrix 70 of FIG. A macro composite material including abrasive particles 66. Single or multiple plate-like particles 66 may be provided along the contact surface 24. In the illustrated embodiment, a plurality of plate-like particles 66 are provided on horizontal ribs 26-5, and the spaces between the plate-like particles define tendrils 68 of metal matrix 70. The facing layers 22, 52, 64 of the cooling elements 12 ', 42 may have the same or similar composition and structure.

Example 6 Foam Containing Abrasion-Resistant Particles The foam disposed on the contact surfaces 24, 54, 58, 62, specifically the open-cell foam, has an infinite interface area, reduced weight, strong It has the advantages of easy bonding, multiple tendrils, and ease of property adjustment due to porosity. Thus, the cooling elements 12, 12 ', 42 with facing layers 22, 52, 64 of macrocomposite material in the form of foam 66 provide advantageous wear properties and ease of property adjustment.

  FIG. 5-6 shows a unit volume 72 of a macrocomposite in the form of a foam including a copper matrix 70 and abrasion resistant particles 66. The dimension a defines the outer size of the composite material unit cell, and is a size of 3 to 50 mm, for example, 3 to 10 mm. The unit volume of a macrocomposite of this size is a material having the properties defined in Table 3. FIG. 2 shows the cooling element 12, in which the facing layer 22 shown at one of the horizontal ribs 26 (reference number 26-6 in FIG. 2) comprises a copper matrix 70 and the foam of FIGS. 5-6. Macro-composite material comprising abrasion-resistant particles 66 formed in the following manner. The facing layers 22, 52, 64 of the cooling elements 12 ', 42 may have the same or similar composition and structure.

Example 7-Mesh Consisting of Abrasion Resistant Particles The mesh disposed on the contact surfaces 24, 54, 58, 62 has a large interfacial area, light weight, and variable friction due to the varying mesh orientation. It has the advantage of biological properties. Accordingly, cooling elements 12, 12 ', 42 with facing layers 22, 52, 64 of macrocomposite material in the form of mesh 66 provide advantageous wear characteristics.

  FIGS. 5-7 illustrate a unit volume 72 of a macrocomposite material that includes a copper matrix 70 and abrasion resistant particles 66 in the form of a mesh. The dimension a defines the outer size of the composite material unit cell 72, and is 3 to 50 mm, for example, 3 to 10 mm. The unit volume of a macrocomposite of this size is a material having the properties defined in Table 3. FIG. 2 shows the cooling element 12, in which the facing layer 22 shown on one of the horizontal ribs 26 (26-7 in FIG. 2) is in the form of a copper matrix 70 and the mesh shown in FIGS. 5-7. It includes a macrocomposite material that includes abrasion resistant particles 66. The facing layers 22, 52, 64 of the cooling elements 12 ', 42 may have the same or similar composition and structure.

Example 8-Abrasion resistant particles in the form of parallel beads Cylindrical beads (hollow cylindrical rods) oriented to have a longitudinal axis parallel to the contact surfaces 24, 54, 58, 62 This is an advantageous tribological shape because the entire length of the cylindrical bead acts as a deflector on the facing surface (the charge). Thus, the cooling elements 12, 12 ', 42 with facing layers 22, 52, 64 of macrocomposite incorporating bead-shaped wear-resistant particles 66 oriented parallel to the contact surfaces 24, 54, 58, 62 In use, they are expected to exhibit low wear rates due to reduced frictional sliding contact between the charge and the contact surfaces 24, 54, 58, 62 of the cooling elements 12, 12 ', 42. Due to the inner diameter, this bead shape results in the formation of additional tendrils 68 in the metal matrix and additional penetration (contact surface area) between the wear resistant particles 66 and the metal matrix 70.

  FIGS. 5-8 illustrate a front surface of a unit volume 72 that includes a copper matrix 70 and cylindrical bead-shaped wear-resistant particles 66 having a diameter a and a length a and that defines the surface 20 of the facing layer 22. Shown is a unit volume 72 of macrocomposite material oriented parallel and forming part of the contact surfaces 24, 54, 58, 62. The dimension a defines the outer size of the composite material unit cell 72, and is 3 to 50 mm, for example, 3 to 10 mm. The unit volume 72 of the macro composite material of this size is a material having the properties defined in Table 3. FIG. 2 shows the cooling element 12, in which the facing layer 22 shown at one of the horizontal ribs 26 (reference number 26-8 in FIG. 2) comprises a copper matrix 70 and the cylindrical beads of FIG. 5-3. It includes a macrocomposite material that includes abrasion-resistant particles 66 in shape. The facing layers 22, 52, 64 of the cooling elements 12 ', 42 may have the same or similar composition and structure.

  As mentioned above, the thickness (or depth) of the facing layers 22, 52, 64 may be from about 3 mm to about 50 mm. To provide sufficient thickness, the facing layers 22, 52, 64 can include either a single layer of abrasion resistant particles within the facing layers 22, 52, 64 or multiple layers stacked one on top of the other.

  According to another aspect, the present disclosure provides for the use of a negative type of cooling element, arranging a designed arrangement of wear resistant particles in a mold cavity, and introducing molten metal into the mold cavity. A method is provided for economically producing a cooling element as described herein.

  The mold may be a conventional sand mold or a permanent graphite mold. The use of a permanent mold is advantageous because it allows the mold to be reused multiple times and can produce castings with better dimensional tolerances. These properties of the permanent mold reduce the cost of manufacturing the mold and the cost of machining, respectively, thereby reducing the cost of manufacturing the cooling element.

  The positioning of the wear-resistant particles in the designed arrangement can be done on site or by using an assembly of pre-assembled assemblies arranged in a mold. The latter is advantageous because it allows for better manufacturing and quality control, bonding of the metal with the wear resistant particles, thermal conductivity, and reduced casting preparation time.

  FIG. 2 shows a cooling element 12 in the form of a blast furnace stave cooler having a corrugated structure with a plurality of uniform horizontal ribs 26 and a plurality of horizontal valleys 28, as disclosed herein. It will be appreciated that embodiments are generally applicable to various aspects, sizes and shapes of cooling elements 12 that undergo wear due to contact with hard abrasive particulate material in a metallurgical furnace. For example, as shown in FIG. 3, the facing layer 22 / contact surface 24 of the stave cooler 12 # has a wide flat surface, but little height or depth. Thereby, the entire contact surface 24 of the stave cooler 12 is exposed so as to be in contact with the descending column 6 (FIG. 1) of the charged material.

  Although FIG. 4 shows a cooling element in the form of a stove cooler 42 for a blast furnace having a conical configuration with a first abutment surface 54, the embodiments disclosed herein generally have various configurations. , A cooling element 42 of size and shape, through coke or another fuel injected through the stave cooler, due to wear and erosion of the inner and outer walls of the stave cooler, and It will be appreciated that the present invention can be applied to devices that wear away due to wear and erosion due to direct contact with the furnace charge consisting of alternating layers of (pellet, massive ore).

  FIG. 7 shows a copper matrix 70 and a cylindrical rod-shaped abrasion resistant extending parallel to the surface 20 of the facing layer 22 described above with reference to FIGS. 2 (ribs 26-3), 2C and 5-3. 14 shows a modified example of the macro composite material including the conductive particles 66. In the embodiment of FIG. 7, the rod-shaped particles 66 are hollow and have internal channels 76 for the flow of the coolant. The ends of the rod-shaped particles 66 are wrapped around the edge of the stave cooler 12 to be connected to the coolant manifold and coolant conduit 18 at a 90 degree angle to the center. Thus, this embodiment provides water cooling to the contact surface of the cooler.

  Although the invention has been described with reference to particular embodiments, the invention is not limited thereto. The invention includes all embodiments that may be within the scope of the following claims.

Claims (52)

An abrasion-resistant material for use on a contact surface of a metallurgical furnace cooling element, wherein the abrasion-resistant material includes a macrocomposite material that includes abrasion-resistant particles.
The wear-resistant particles are repeatedly arranged in a pattern defining a space therebetween,
The wear-resistant material, wherein the space is formed with a tendrill having a uniform thickness in a length direction of the first metal by invading the first metal.   The wear-resistant particles are comprised of one or more wear-resistant materials selected from ceramics, including carbides, nitrides, borides and / or oxides, wherein the first metal is substantially The wear-resistant material according to claim 1, wherein the wear-resistant material comprises a heat conductive metal. The carbide is selected from the group consisting of tungsten carbide, niobium carbide, chromium carbide and silicon carbide,
The nitride is selected from the group consisting of aluminum nitride and silicon nitride,
The oxide is selected from the group consisting of aluminum oxide and titanium oxide,
The boride is selected from the group consisting of silicon boride, and / or the substantially thermally conductive material comprises stainless steel, copper, and copper alloys including copper-nickel alloys such as cupronickel alloys The wear-resistant material according to claim 1 or 2, which is selected from the group.   The wear-resistant material according to any one of claims 1 to 3, wherein the macro-composite material has an abrasive wear rate of 0.6 times or less the abrasive wear rate of gray cast iron under the same conditions.   The wear-resistant material according to any one of claims 1 to 4, wherein the wear-resistant particles have a size of 3 mm to 10 mm.   The macro-composite material has an outer size of 3 mm to 50 mm, and the outer size is defined as a length of a side of a cube defining a unit volume of the macro-composite material. A wear-resistant material according to claim 1.   The wear-resistant material according to any one of claims 1 to 6, wherein the wear-resistant material has a thickness of 3 mm to 50 mm.   The wear-resistant material according to claim 6, wherein a frontal area filling rate of the wear-resistant particles in the unit volume of the macrocomposite material is 20 to 100%.   9. The method according to claim 5, wherein an interface area between the wear-resistant particles and the first metal is at least 0.25 times a surface area of the unit volume of the macrocomposite material. 10. Abrasion resistant material as described.   10. The method according to any one of claims 5 to 9, wherein a contact surface area between the wear-resistant particles and the first metal per unit volume of the macrocomposite material is at least 0.1. Abrasion resistant material.   The wear-resistant material of claim 1, wherein the wear-resistant material and the space therebetween are each substantially identical.   The wear-resistant material according to claim 11, wherein at least some of the metal tendrils are formed in the spaces between the wear-resistant particles.   13. The method of any of the preceding claims, wherein any of the abrasion resistant particles disposed on the front surface extend into the macrocomposite material by at least 0.25 of its length or diameter. Abrasion resistant material as described.   14. A wear-resistant material according to any of the preceding claims, wherein each of the wear-resistant particles has a cylindrical shape.   15. The wear-resistant material according to claim 14, comprising a single layer of said wear-resistant particles packed in a packing arrangement of hexagonal regions, provided on a contact surface.   15. The wear-resistant material of claim 14, wherein each of the cylindrical wear-resistant particles has a longitudinal axis disposed perpendicular to a hitting surface formed by the wear-resistant particles.   The wear-resistant material of claim 14, wherein each of the cylindrical wear-resistant particles has a longitudinal axis disposed parallel to a hitting surface formed by the wear-resistant particles. Wherein each of the cylindrical wear resistance particles have a hollow interior formed with the metal tape Ndoriru unit is entering the first metal, abrasion-resistant material according to claim 16 or 17.   The macro-composite material comprises plate-shaped wear-resistant particles, wherein the surface of each of the plate-shaped wear-resistant particles forms a part of the contact surface. Abrasion resistant material as described.   20. The abrasion resistant material of claim 19, wherein the space between the surfaces of the plate-like particles that make up the abutment surface defines the first metal tendril.   14. A wear-resistant material according to any of the preceding claims, wherein the macrocomposite material is comprised of foam or mesh wear-resistant particles.   The wear-resistant material of claim 1, wherein at least a portion of the tendril surrounds the wear-resistant particles and extends parallel to the contact surface defined by the wear-resistant particles. A cooling element for a metallurgical furnace,
The cooling element includes a main body including a first metal;
Having a facing layer that provides a hitting surface to the cooling element,
The facing layer is made of a composite material,
The composite material includes abrasion resistant particles;
The wear-resistant particles are arranged in a repeating pattern defining a space therebetween, the space being penetrated by a second metal, the second metal having a uniform thickness along its length. Forming a tendril with
Cooling element.   24. The cooling element of claim 23, wherein all of the wear resistant particles are substantially identical.   24. The cooling element of claim 23, wherein the space between all of the wear resistant particles is substantially identical.   24. The cooling element according to claim 23, wherein the space between the wear-resistant particles is completely penetrated by the second metal.   27. The cooling element according to any one of claims 23 to 26, wherein the wear-resistant particles have a hardness of at least 6.5 Mohs.   28. The wear resistant particle of claim 23-27, wherein the wear resistant particles of the facing layer comprise one or more wear resistant materials selected from ceramics including carbides, nitrides, borides and / or oxides. The cooling element according to claim 1. The carbide is selected from the group consisting of tungsten carbide, niobium carbide, chromium carbide and silicon carbide;
The nitride is selected from the group consisting of aluminum nitride and silicon nitride;
29. The cooling element according to claim 28, wherein said oxide is selected from the group consisting of aluminum oxide and titanium oxide, and / or said boride is selected from the group consisting of silicon boride.   30. The cooling element according to any one of claims 23 to 29, wherein the second metal is a metal of the same type as the first metal.   31. The cooling element according to any one of claims 23 to 30, wherein the second metal is selected from the group consisting of cast iron, steel including stainless steel, copper, and copper alloy including copper-nickel alloy.   32. The cooling element of any one of claims 23 to 31, wherein the second metal is a high copper alloy having a copper content of at least 96 weight percent.   33. The cooling element according to any one of claims 23 to 32, wherein the composite material has an abrasive wear rate of 0.6 times or less that of gray cast iron under the same conditions.   The cooling element according to any one of claims 23 to 33, wherein the facing layer has a thickness of 3 mm to 50 mm.   35. The cooling element according to any one of claims 23 to 34, wherein the space between the wear-resistant particles defines at least a portion of the second metal tendril.   36. The cooling element of claim 35, wherein the wear-resistant particles have a size between 3mm and 10mm. The Te Ndoriru extends toward the contact surface, cooling device according to any one of claims 23 to 36.   The cooling element according to any one of claims 23 to 37, wherein the tendrill forms a part of the contact surface.   39. Any of the claims 23-38, wherein any of the abrasion resistant particles located at the abutment surface extend into the composite by at least 0.25 of its length or diameter. Cooling element.   40. The cooling element according to any one of claims 23 to 39, wherein at least a portion of the tendril surrounds the wear-resistant particles and extends toward the abutment surface.   The cooling element according to any one of claims 23 to 40, wherein the abrasion-resistant particles are independently arranged.   24. The cooling element of claim 23, wherein the facing layer comprises a single layer of the abrasion resistant particles packed in a packing arrangement of hexagonal regions.   24. The cooling element of claim 23, wherein the wear-resistant particles are cylindrical and each of the wear-resistant particles has a longitudinal axis perpendicular to the abutment surface.   24. The cooling element of claim 23, wherein the wear-resistant particles are cylindrical, and each of the wear-resistant particles has a longitudinal axis parallel to the abutment surface.   45. The cooling element of claim 43 or 44, wherein each of the cylindrical wear-resistant particles has a hollow interior penetrated by the second metal.   24. The cooling element according to claim 23, wherein the wear-resistant particles include plate-shaped wear-resistant particles, and a surface of the plate-shaped wear-resistant particles forms a part of the contact surface.   47. The cooling element of claim 46, wherein the space between each of the surfaces of the plate-like wear-resistant particles, defining the abutment surface, defines the tendril of the second metal.   24. The cooling element of claim 23, wherein the wear-resistant particles are comprised of foamable or mesh-like particles.   49. The cooling element according to any one of claims 23 to 48, wherein the body is provided with one or more internal cavities that define one or more internal coolant flow paths. A method for manufacturing a cooling element of a metallurgical furnace, comprising:
(A) arranging the wear-resistant particles in a repeated pattern having a space therebetween;
(B) locating the wear-resistant particles in a region of a mold cavity defining the facing layer of the cooling element;
(C) introducing a molten metal into the mold cavity corresponding to the wear-resistant particles having a repetitive pattern disposed in the mold cavity and allowing the molten metal to enter the space between the wear-resistant particles; Forming a metal tendril having a uniform thickness in its length direction;
A method that includes   51. The method of claim 50, wherein the repeated pattern of wear-resistant particles is provided in step (a) in the form of a pre-fabricated assembly.   24. The cooling element of claim 23, wherein the space between the wear-resistant particles defines at least a portion of the tendril of the second metal.

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